The pain that Mark Duncan experienced when a cottonmouth moccasin bit him on his calf in April was unlike any he had experienced before.

"It was like you took a hammer and hit me as hard as you could," he said, adding that he had a lot of bleeding plus paralysis in his calf, extreme sweating and heart palpitations after he was bitten.

The cottonmouth bit him near his home near Ridgeway as he was walking along a fence line. It was lying in the grass and, while the cottonmouth is a type of water moccasin, it was at least 40 feet from water, he said.

"It was an aggressive snake," Duncan recalled. Although he tried to get away from the cottonmouth, "it came after me" and bit him on its second try.

Richard Hoffman, director of research and collections at the Virginia Museum of Natural History in Martinsville and a snake expert, said most snakes - even poisonous ones - generally are docile and will try to flee if they see someone coming or sense a person is around.

"They're more afraid of us than we are afraid of them," Hoffman said.

He also said that as far as he knows, no cottonmouths are in this area.

"There's at least one," said Duncan, who was unable to kill the snake that bit him. He grew up in eastern North Carolina, where cottonmouths are common, and he said he knows what a cottonmouth looks like.

Information on the Internet showed that cottonmouths are found from Virginia south to Florida and west toward Texas, Oklahoma and Kansas.

According to that information, the cottonmouth is the only poisonous water snake in America but sometimes it is hard to tell cottonmouths apart from other types of water snakes that are not poisonous.

Cottonmouths have brown, green or black bodies with light yellow bellies and distinctive crossbands circling their bodies. Their colors tend to become less vibrant as they grow older. They typically are about 30 inches long but some have been measured at more than six feet long. When they are not in the water, they tend to lie on logs, rocks or limbs nearby.

Unlike other types of venomous snakes that tend to make quick strikes, cottonmouths are better able to latch onto their victims and inject larger amounts of venom, so they are especially dangerous.

A cottonmouth usually lies coiled up with its head held back and its mouth open. That exposes the white tissue in its mouth - which is what gives the snake its name. Duncan said he clearly saw the white mouth of the one that bit him.

LOCAL POISONOUS SNAKES

Hoffman said about two dozen species of snakes are in the Henry County-Martinsville area. Most are not poisonous, he said. The two prevalent types that are poison are copperheads and rattlesnakes.

No other snake in Virginia looks like the copperhead, said Hoffman. It is copper-colored with unique hour glass-shaped markings. Those markings resemble thread spools to some people, he indicated.

Locally, rattlesnakes are mostly seen in the Snow Creek and Turkey Cock Mountain areas, as well as around Fairystone State Park, information from Hoffman and the Internet shows.

Their varied colors help them blend into their surroundings, and often a person will hear them shake their rattles - as a warning not to get close - before seeing them, so the person can get away, according to Hoffman.

Generally, "you're very unlikely to get bit by a snake," he said, adding that people are more apt to be struck by lightning than suffer a snakebite.

About 150 deaths from snakebites occur nationwide each year, Hoffman said. Most are due to rattlesnake bites, he said.

However, "you're very, very unlikely to get bit by a rattlesnake" because of its rattle to warn of its presence, he emphasized.

WHAT TO DO IF YOU'RE BITTEN

Don't panic if you see a snake. Don't even panic if you are bitten by one.

Panicking can alarm a snake, causing it to strike and venom to circulate in a person's body more quickly, said Hoffman, who also is the museum's curator of recent invertebrates.

Nonpoisonous snakes have small teeth and cause little more than a scratch when they bite, he said. If someone is bitten by a nonpoisonous snake, "wash it off and forget about it," he said.

In the past, routine practice for dealing with bites from poisonous snakes was to use a tourniquet to cut off the blood supply to the affected limb, as well as to make cuts around the wound and suck out venom. Doctors have since determined that can cause more harm than good. For instance, using tourniquets for too long can cause body tissue to die.

To treat a poisonous snakebite, Hoffman recommends putting ice on it if possible and "move as slowly as possible" to slow the venom's circulation. Seek medical attention immediately, he emphasized.

Don't go deep into the mountains, far from a doctor's office or hospital, alone. Urgent medical attention is crucial in treating poisonous snakebites. Anyone who is bitten and cannot get medical help soon had better "cross your fingers and pray," Hoffman advised.

If possible, people should kill a poisonous snake that bites them - or have someone else kill it. Hoffman said snakes that have bitten someone tend to not move far from the location of the bite.

The dead snake should be put in a container and transported to the hospital with the victim so doctors can try to identify it, Hoffman said. Identifying the snake will help doctors determine the type of antivenom to use when treating the bite, he said.

However, a physician associated with the University of Virginia Medical Center said recently that is not needed. Doctors can tell a snakebite without seeing the snake, he said.

Hoffman said the best way to try and prevent snake bites basically is to use common sense. For example: